Field of the Invention
This disclosure relates to the field of display technologies, and in particular, to an array substrate, a display device, and a method for driving the display device.
Description of the Prior Art
A thin film transistor-liquid crystal display (TFT-LCD), which has advantages of stable image, image fidelity, radiation annihilation, and space and energy saving, is widely applied to electronic products such as television sets, mobile phones, and computer monitors. At present, TFT-LCDs are leading in the flat-panel display field.
A basic image display unit of a liquid crystal display panel is sub-pixel. The sub-pixel may create a capacitance effect in the structure of the liquid crystal display panel. As long as sufficient drive voltages are applied between two ends of the capacitor, image may be displayed. The voltages applied to the two ends of the capacitor are respectively a common voltage and a data voltage. Therefore, if no positive-negative polarity inversion is conducted for the voltages applied to the two ends of the capacitor, sub-pixels for image display are long-term charged by a DC voltage having the same polarity, and thus a specific amount of charges may be accumulated on a liquid crystal alignment layer and a liquid crystal layer between common electrodes and pixel electrodes, as illustrated in FIG. 1. In this way, the sub-pixel has a poor display effect. Even worse, liquid crystal polarization may be caused and consequently the sub-pixel may fail. The failure of this sub-pixel to the least extent may cause an afterimage, i.e., background color on the display image, on the liquid crystal display panel, and color contrast may be degraded. Therefore, the voltages applied to the two ends of the capacitor need to be subject to polarity inversion at intervals of a specific time period.
In the prior art, polarity inversion driving methods mainly comprise frame inversion, row inversion, point inversion and the like. For example, in the N−1th frame, all sub-pixels have a positive polarity; in the Nth frame, all sub-pixels have a negative polarity; and in the N+1th frame, all sub-pixels have a positive polarity, and so on. This is referred to as the frame inversion driving method. Still for example, as illustrated in FIG. 2, in the N−1th frame, all sub-pixels in odd rows have a positive polarity and all sub-pixels in even rows have a negative polarity; in the Nth frame, all sub-pixels in odd rows have a negative polarity and all sub-pixels in even rows have a positive polarity; and in the N+1th frame, all sub-pixels in the odd rows have a positive polarity and all sub-pixels in the even rows have a negative polarity, and so on. This is referred to as the row inversion driving method. Yet still for example, in a frame, polarities of any two adjacent sub-pixels are inversed, which is referred to as the point inversion driving method. In the frame inversion driving method, the drive voltages are too great, the power consumption is high, and the flicker phenomenon is severe; whereas in the point inversion driving method, the circuit is too complicated and the driving control is relatively troublesome. Therefore, the row inversion driving method having smaller driving voltages and lower power consumption is widely applied.
In the prior art, the row inversion driving method is generally implemented by inversing a common voltage of each row of sub-pixels, i.e., keeping the polarity of the data voltage unchanged. However, the common voltage is subject to alternate polarity changes, and therefore the data voltage is subject to positive-negative alternate changes with respect to the common voltage. Nevertheless, since the data voltage and the common voltage applied to adjacent sub-pixels in the same row have the same polarity and the adjacent sub-pixels are very close to each other, mutual impacts may be caused between the adjacent sub-pixels, and crosstalk may occur, thereby resulting in the Mura phenomenon and affecting the image display effects.